Hey Howie, I pop in every now and again..
It'll take about three years for the guy to hit stride so I can back out. I'm gonna hafta learn C++ to help him code the motion algorithms for the superconducting magnet winder and learn the physical processes.
Now I gotta find someone to be a cold diode expert, and another to code SOTA motion control in another division. Been watching the motion industry, they are starting to understand some of the things we've been doing, so I suspect the younguns comin out will be able to learn. The guys a decade out of mechatronics don't seem to have really learned control theory. The mention of bode or phase margin gets the "deer in the headlight look". And some of the erroneous concepts need to be unlearned..now they stress using an inverted plant transfer function for the feedforwards, but that doesn't work when the device is highly non linear..
This speaker magnetic discussion, just wow..
Now a fun project...I picked up an Incra miter 1000/HD for good picture frame miter cuts..only to find my table saw doesn't cut a really good straight line. Turns out the blade was wobbling. Bought a new arbor, needle bearing, and housing. Correctly determined it was the needle bearing, now putting it back together. It's amazing what you can find on the net now.
Jn
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JN,
As I think you learned table saw bearings wear out. The standard test is to cut halfway through a test board with the blade at full height. Then flip the board over and cut in from the other side with the blade's teeth just clearing the test piece. If the bearing is good the cuts will match where they come together.
If buying a used table saw doing this test in front of the seller should knock quit a bit off the asking price! I did get a deal on a CNC router with just a machinist's level.
As I think you learned table saw bearings wear out. The standard test is to cut halfway through a test board with the blade at full height. Then flip the board over and cut in from the other side with the blade's teeth just clearing the test piece. If the bearing is good the cuts will match where they come together.
If buying a used table saw doing this test in front of the seller should knock quit a bit off the asking price! I did get a deal on a CNC router with just a machinist's level.
Interesting..
I usually just clear the work with the blade so I can count to ten at the end of the day, and that is when I spotted the problem. So I did another pass with the blade as proud as it could be, thinking that the direction of the forces being more vertical would clear it up, as opposed to mostly horizontal which turns the blade. Alas, it did appear slightly better, but the angle wasn't exact anyway regardless of feed rate.
I really didn't like having a 4 inch blade that high when cutting 3/4 maple. I still have to run it about an inch proud anyway, otherwise it chips out the top trailing edge. I may have to make a zero clearance plate to prevent lower edge chipout though.
When I removed the front housing from the motor, I noted that the arbor would rock a bit when I torqued the end of it, but no rocking at all when I torqued it close to the sealed exit bearing. So figured it was the needle bearing deep inside. The existing arbor was below .0002 from the new replacement arbor at the needle bearing surface, so I just used the old one.
Getting ready to try it. If it works well, I'll buy two more needle bearings and store em.
ps.. just ordered two build plates for my CR10s, find large builds just pull the tape right off the surface and distort the edges upward. Amazon was kind enough to find me build plates that will handle ABS temperatures. I love how the tech keeps getting better. Now if they would just keep more silver PLA in stock, I'm burning a kilo a day.
jn
I usually just clear the work with the blade so I can count to ten at the end of the day, and that is when I spotted the problem. So I did another pass with the blade as proud as it could be, thinking that the direction of the forces being more vertical would clear it up, as opposed to mostly horizontal which turns the blade. Alas, it did appear slightly better, but the angle wasn't exact anyway regardless of feed rate.
I really didn't like having a 4 inch blade that high when cutting 3/4 maple. I still have to run it about an inch proud anyway, otherwise it chips out the top trailing edge. I may have to make a zero clearance plate to prevent lower edge chipout though.
When I removed the front housing from the motor, I noted that the arbor would rock a bit when I torqued the end of it, but no rocking at all when I torqued it close to the sealed exit bearing. So figured it was the needle bearing deep inside. The existing arbor was below .0002 from the new replacement arbor at the needle bearing surface, so I just used the old one.
Getting ready to try it. If it works well, I'll buy two more needle bearings and store em.
ps.. just ordered two build plates for my CR10s, find large builds just pull the tape right off the surface and distort the edges upward. Amazon was kind enough to find me build plates that will handle ABS temperatures. I love how the tech keeps getting better. Now if they would just keep more silver PLA in stock, I'm burning a kilo a day.
jn
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I bet Peter Gabriel was a good teacher. Have you also learned how to sell England by the pound?
No but I think Boris has!
Personally I think Gabriel's first solo album suggests he was more than ready to branch out anyway. Had he realised he would unleash Phil Collins on the world he might not have 🙂
Personally I think Gabriel's first solo album suggests he was more than ready to branch out anyway. Had he realised he would unleash Phil Collins on the world he might not have 🙂
Put the saw back together, spins in the right direction, go figure.😀 and no wobble..time to buy two sets of spare bearings..
Ps... I will have all of you note....there were no leftover parts....a first for me...
Setup the incra, tomorrow some test cuts.
Rather annoyed with the incra, they have nylon washers that expand to get the fixture snug in the slots, but the torque required was way too high.. the nylon washers need material removed because they are too constrained and fight expansion. Will revisit that at a later date. I may have to put the incra into my mill and open the cavities the nylon washer sits in, as dropping the washer diameter won't do it.
I have to say, I purchased bondhause allen wrenches, they are absolutely great. The allen incra supplied actually twisted plastically with the torque needed, the bondhause.. piece of cake.
Jn
Ps... I will have all of you note....there were no leftover parts....a first for me...
Setup the incra, tomorrow some test cuts.
Rather annoyed with the incra, they have nylon washers that expand to get the fixture snug in the slots, but the torque required was way too high.. the nylon washers need material removed because they are too constrained and fight expansion. Will revisit that at a later date. I may have to put the incra into my mill and open the cavities the nylon washer sits in, as dropping the washer diameter won't do it.
I have to say, I purchased bondhause allen wrenches, they are absolutely great. The allen incra supplied actually twisted plastically with the torque needed, the bondhause.. piece of cake.
Jn
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Tolerance should be .0005" so things should be OK. I have some aluminum Incra parts around here. The stay straight as a banana. Only advantage is if you acidentally score them with a blade, they don't damage it. (Bought them as a closeout quite cheaply.)
Of course if you use a blade the way it used to be taught with the teeth just clearing the work piece all you get for being careless is a scar. With the blade higher you can get two thumbs or pieces of them. My current saw has a functional floating blade guard and is a Felder moving table saw. So you have to be rather foolish/stupid to spout blood. But the rule here still stands; blood only-closer hospital to the right out of the lot, extra pieces left out of the lot to the highly rated emergency room that keeps enough staff at all times to put you back together.
One of those construction site rules always know where to go and how to alert them in advance.
Of course if you use a blade the way it used to be taught with the teeth just clearing the work piece all you get for being careless is a scar. With the blade higher you can get two thumbs or pieces of them. My current saw has a functional floating blade guard and is a Felder moving table saw. So you have to be rather foolish/stupid to spout blood. But the rule here still stands; blood only-closer hospital to the right out of the lot, extra pieces left out of the lot to the highly rated emergency room that keeps enough staff at all times to put you back together.
One of those construction site rules always know where to go and how to alert them in advance.
JN,
Stay away from Wiha tools, they are just too good and will spoil you.
But you are about to violate Murphy's law. If you have spare parts, you will not be able to find them when needed!
Stay away from Wiha tools, they are just too good and will spoil you.
But you are about to violate Murphy's law. If you have spare parts, you will not be able to find them when needed!
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Indeed. My thought exactly after reading two posts when I ventured back for a quick stroll through this thread.
I saw PG solo on the Security tour in '83...and he was fantastic, with Jerry Marotta, David Rhodes, Tony Levin and Larry Fast...what a band! He had this really amazing effect in the song 'San Jacinto,' as best as I can guess he had a small mirror in his hand, and a laser at his feet pointing upwards. When he started the refrain he thrust his had out at a 45° angle and it looked for all the world like he had a laser coming out of his hand...very dramatic and amazing effect, the audience roared...I remember going "Whoaa!!" and getting goose bumps.
Speaking of selling, I have learned how to sell TO England by the pound...the great Waters & Stanton are one of my distributors in the UK!
Cheers,
Howie
I was going to respond to this because I struggle often to work out what a sentence id trying to convey, but I though it may be interpreted as my being rude.
Sentence structure is crucial to conveying accuracy of meaning, and fine nuances certainly can be lost if rules are not adhered to.
My dad recently got a 1000HD and it's been fantastic*. I'm curious what issues you're having! Wonder if it's somehow a different connection setup.
*I recently moved and am sorely missing using his shop. Sorely. And glad I can count to ten.
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Being separated by a common language, sometimes we trip over intent and meaning.
Have no concern w/r to me.. if you think I was rude, please say so...no problem..
Jn
The expanding washers were not able to easily open to the point where there was zero slop. I am sure I measured the slots and they were within the specs on the incra. Perhaps it is just more difficult when the slots are on the outer limits of the spec. The actual problem is that the washers are tight to the milled cavity they sit in, so when tightening the screw, the bulk of the washer hits the cavity walls so resists further expansion. If I could just open the cavity maybe 200 or 300 microns, that would allow the washers to reach the slot walls. I will have to measure the diameter of the cavity to figure out what end mill I should use.
I love the incra, I just may have to do some mods to make it really good with my saw. As a worst case, I could see machining a new steel center strip with dimensions closer to my slots. Hey, I have the mill, might as well use it.. making it to within 15 or 20 microns is no big deal. But I really love the tenths of a degree capability.
Jn
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JN
The guide slots are usually ground for accuracy. I used to use precision ground flat stock when I needed to fit something.
My current saw with a moving table has a built in cross arm with a protractor. Notched each 5 degrees with precision adjusting stops. But just the printed scale for in between. As the arm goes to better than 8' the accuracy is adequate.
I haven't had issues with the nylon shoulder washers not fitting. My suggestion is store them in the freezer and keep the metal bits a bit warm before assembly.
My simonsound website does have some pictures of my tools.
The guide slots are usually ground for accuracy. I used to use precision ground flat stock when I needed to fit something.
My current saw with a moving table has a built in cross arm with a protractor. Notched each 5 degrees with precision adjusting stops. But just the printed scale for in between. As the arm goes to better than 8' the accuracy is adequate.
I haven't had issues with the nylon shoulder washers not fitting. My suggestion is store them in the freezer and keep the metal bits a bit warm before assembly.
My simonsound website does have some pictures of my tools.
The saw was my fathers, so it saw lots of duty. If I have to do some flat stock, so be it..
The funny thing...I have a makita I use for precision cuts, but when the incra came in I found that the slots were not .75 inches wide...what??? I thought slots were standard..
I recall a sled that the incra can lock into, you pass it through to get a zero clearance surface for the work. Forgot the name and I can't find it in the rockler catalog. Perhaps it was online..
Ps..ah yes, online. The incra miterexpress. I just have to remeasure the slots in the table, they say a range of .740 to .760
Jn
The funny thing...I have a makita I use for precision cuts, but when the incra came in I found that the slots were not .75 inches wide...what??? I thought slots were standard..
I recall a sled that the incra can lock into, you pass it through to get a zero clearance surface for the work. Forgot the name and I can't find it in the rockler catalog. Perhaps it was online..
Ps..ah yes, online. The incra miterexpress. I just have to remeasure the slots in the table, they say a range of .740 to .760
Jn
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I provide some clarity...
Back EMF is the voltage created by the vc moving in the gap. It has various components, like actual velocity (faraday's law of induction) and the voltage produced when a current carrying conductor with a magnetic field moves such that the inductance changes (this is the Idl/dt component I mentioned earlier).
A voltage is NOT an impedance, period. A back EMF is a voltage.
Impedance is the relationship between the voltage driving the system and the current the system draws from that voltage. And there is a phase and magnitude associated with it.
A speaker is interesting in that below resonance the "impedance" phase shifts into the capacitive domain, this due to the cone mass.
A speaker is interesting in that the voice coil velocity introduces dissipative losses due to eddy current dragging through the iron pole piece.
A speaker is interesting in that a speaker vc inductance is dependent on position in the gap, as well as velocity in the gap (a term nobody I have read understands) as well as the transfer function being acceleration dependent (well outside what is currently understood).
I do not engage that person because nothing can be gained by such..
Jn